Systems and Methods For Inductive Subsea Hydrocarbon Pipeline Heating For Pipeline Remediation

ABSTRACT

Systems and methods for inductively heating a subsea hydrocarbon pipeline. These systems and methods may include the use of a mobile subsea hydrocarbon pipeline heating assembly to remediate the formation of an obstruction within the subsea hydrocarbon pipeline. The mobile subsea hydrocarbon pipeline heating assembly may include a mobile subsea conveyance, which may be configured to traverse a selected portion of the subsea hydrocarbon pipeline, and an inductive heating element, which may be configured to inductively heat an inductively coupled portion of the subsea hydrocarbon pipeline.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of U.S. Provisional Patent Application 61/550,738 filed Oct. 24, 2011 entitled SYSTEMS AND METHODS FOR INDUCTIVE SUBSEA HYDROCARBON PIPELINE HEATING FOR PIPELINE REMEDIATION, the entirety of which is incorporated by reference herein.

FIELD OF THE INVENTION

The present disclosure is directed to systems and methods for inductively heating subsea hydrocarbon pipelines, and more particularly to systems and methods for using inductive heating to remediate the formation of obstructions within subsea hydrocarbon pipelines.

BACKGROUND OF THE INVENTION

The formation of solids and/or deposits within a hydrocarbon pipeline may produce obstructions, or occlusions. These obstructions may increase a resistance to fluid flow within the hydrocarbon pipeline, leading to an increase in pumping costs, and/or limit a flow of fluid within the hydrocarbon pipeline, decreasing the fluid-carrying capacity of the hydrocarbon pipeline. Moreover, these obstructions, if permitted to continue to grow, or propagate, may even completely obstruct, or clog, a portion of the hydrocarbon pipeline, thereby precluding fluid flow therethrough until the obstruction is removed.

The fluid present within a hydrocarbon pipeline may include a variety of components, illustrative, non-exclusive examples of which include hydrocarbons, oil, crude oil, wax, asphaltenes, resins, aromatic hydrocarbons, alkanes, alkenes, alkynes, natural gas, and/or water. Under conditions of appropriate temperature, pressure, and/or chemical composition, a portion of these components may solidify, precipitate, and/or otherwise separate from the bulk of the fluid to produce solid, solid-like, gel, and/or gel-like formations (collectively referred to herein as solids, deposits, and/or solids deposits) that may, alone and/or in combination, produce the obstructions.

As an illustrative, non-exclusive example, waxes often may be found in crude oil. These waxes may deposit on an inner surface, or wall, of the hydrocarbon pipeline due to a variety of thermal and/or surface chemical factors. As an illustrative, non-exclusive example, wax deposits may form when a temperature of the oil and/or a temperature of the inner surface of the hydrocarbon pipeline falls below the wax appearance temperature (WAT) for the particular wax(es) present within the crude oil. This deposition may build-up with time, eventually producing a significant obstruction of the hydrocarbon pipeline. This build-up often may be slow and it is typically removed on a periodic basis to decrease pipeline obstruction due to wax formation.

As another illustrative, non-exclusive example, solid hydrates may form from the combination of water with organic molecules present within the fluid, such as through the combination of water and natural gas molecules. Hydrate formation temperatures and kinetics are dependent on pressure, as well as on the chemical composition of the materials from which the hydrate is formed, and the hydrates may adhere to the inner surface of the hydrocarbon pipeline and/or may form within the fluid flow. The formation of hydrates and the subsequent hydrocarbon pipeline obstruction may, under certain conditions, be much faster than the formation of waxes. Thus, environmental and/or chemical conditions within the hydrocarbon pipeline may be monitored and/or controlled in order to decrease a potential for hydrate formation.

The formation of solids within the hydrocarbon pipeline may be decreased, slowed, prevented, and/or avoided through control of the conditions within the hydrocarbon pipeline. This may include control of the temperature and/or pressure within the hydrocarbon pipeline, as well as control of the chemical composition of the fluid that flows therethrough.

As an illustrative, non-exclusive example, and when the inlet temperature of the fluid flowing into the pipeline is above a threshold temperature at which solids may form, the formation of solids within the hydrocarbon pipeline may be slowed and/or prevented through the use of insulation to limit thermal communication between the fluid within the pipeline and the ambient environment surrounding the hydrocarbon pipeline, and thereby maintain the fluid temperature above the threshold temperature. However, this strategy may only be cost-effective with relatively high fluid inlet temperatures and/or relatively short hydrocarbon pipeline lengths.

As another illustrative, non-exclusive example, hydrate formation may be slowed and/or prevented through the addition of thermodynamic inhibitors, such as ethylene glycol and/or methanol, kinetic hydrate inhibitors, and/or anti-agglomerates to the fluid. However, these chemicals may be costly to obtain, mix with the fluid, and/or recover from the fluid. In addition, if a hydrate blockage has already occurred and there is little or no fluid flow within the hydrocarbon pipeline, inhibitors and/or anti-agglomerates may be ineffective at removing the hydrate blockage and/or it may be difficult to transport the inhibitors and/or anti-agglomerates to the hydrate blockage.

As yet another illustrative, non-exclusive example, the pressure within the pipeline may be lowered in order to decrease the hydrate formation temperature. However, there is a practical limit to the amount that the pressure may be decreased without impacting fluid flow through the hydrocarbon pipeline.

Solids that are already present within the hydrocarbon pipeline may, in some cases, be removed by lowering the pressure within the pipeline. Additionally or alternatively, the solids may be removed from the hydrocarbon pipeline by “pigging.” Pigging includes the insertion and/or transport of a device into the hydrocarbon pipeline that mechanically scrapes away and/or removes solids from the inner surface of the hydrocarbon pipeline. These solids may then be carried down the hydrocarbon pipeline with the flow of fluid. However, pigging may be inefficient, may require the installation of parallel hydrocarbon pipelines to enable the process and/or to avoid interruption of fluid flow during the pigging process, and/or may simply relocate removed solids further downstream within the hydrocarbon pipeline, where they may form another obstruction.

When the hydrocarbon pipeline is not readily accessible, such as may be the case with a subsea hydrocarbon pipeline that is located beneath the surface of a body of water, the limitations of the above approaches to the prevention of solids formation and/or solids removal may be compounded. Additionally or alternatively, when the hydrocarbon pipeline is present within a cold environment, such as an arctic environment and/or a subsea arctic environment, it may not be feasible to utilize insulation alone to maintain the fluid temperature above the threshold solids-formation temperature. Thus, there exists a need for improved systems and methods for remediating the formation of solids within subsea hydrocarbon pipelines.

SUMMARY OF THE INVENTION

Systems and methods for inductively heating a subsea hydrocarbon pipeline. These systems and methods may include the use of a mobile subsea hydrocarbon pipeline heating assembly to remediate the formation of obstructions within the subsea hydrocarbon pipeline. The mobile subsea hydrocarbon pipeline heating assembly may include a mobile subsea conveyance, which may be configured to traverse a selected portion of the subsea hydrocarbon pipeline, and an inductive heating element, which may be configured to inductively heat an inductively coupled portion of the subsea hydrocarbon pipeline.

In some embodiments, the mobile subsea conveyance includes a remotely operated vehicle and/or a propulsion mechanism. In some embodiments, the inductively coupled portion of the subsea hydrocarbon pipeline includes a sub-portion of the selected portion of the subsea hydrocarbon pipeline.

In some embodiments, the selected portion of the subsea hydrocarbon pipeline is determined based at least in part on a variable associated with the selected portion of the subsea hydrocarbon pipeline. In some embodiments, the variable associated with the selected portion of the subsea hydrocarbon pipeline includes a temperature and/or a pressure of the selected portion of the subsea hydrocarbon pipeline.

In some embodiments, the selected portion of the subsea hydrocarbon pipeline is determined based at least in part on a model of the subsea hydrocarbon pipeline. In some embodiments, the model is configured to predict the formation of an obstruction within the subsea hydrocarbon pipeline. In some embodiments, the mobile subsea hydrocarbon pipeline heating assembly is configured to melt obstructions within the pipeline.

In some embodiments, the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without physical, mechanical, electrical, and/or thermal contact between the inductive heating element and the subsea hydrocarbon pipeline. In some embodiments, the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline through an external coating without damage to the external coating. In some embodiments, the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline while a hydrocarbon and/or other fluid is flowing through the subsea hydrocarbon pipeline.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of illustrative, non-exclusive examples of hydrocarbon production systems including the systems and methods according to the present disclosure.

FIG. 2 is a schematic representation of illustrative, non-exclusive examples of subsea hydrocarbon pipelines that may include an obstruction and may be utilized with the systems and methods according to the present disclosure.

FIG. 3 is a schematic representation of illustrative, non-exclusive examples of mobile subsea hydrocarbon pipeline heating assemblies according to the present disclosure.

FIG. 4 is a less schematic representation of another illustrative, non-exclusive example of a mobile subsea hydrocarbon pipeline heating assembly according to the present disclosure.

FIG. 5 is a schematic cross-sectional view of additional illustrative, non-exclusive examples of mobile subsea hydrocarbon pipeline heating assemblies according to the present disclosure.

FIG. 6 is flowchart depicting methods according to the present disclosure of removing obstructions from a subsea hydrocarbon pipeline.

DETAILED DESCRIPTION AND BEST MODE OF THE INVENTION

FIG. 1 provides illustrative, non-exclusive examples of hydrocarbon production systems 10 that include and/or may be utilized with the systems and methods according to the present disclosure. A hydrocarbon production system 10 includes a subsea hydrocarbon pipeline 50 that is located beneath the surface of a body of water 15 and that may be in fluid communication with both a hydrocarbon source 20 and one or more pieces of hydrocarbon recovery equipment 30, with the hydrocarbon production system being configured to transmit a fluid 60 therebetween. Hydrocarbon production systems 10 according to the present disclosure also may include, be associated with, interact with, be in thermal communication with, be in magnetic communication with, and/or be remediated by one or more mobile subsea hydrocarbon pipeline heating assemblies (MHA) 100 that are configured to traverse and heat at least a selected portion of subsea hydrocarbon pipeline 50 to remove and/or remediate obstructions within the pipeline.

Hydrocarbon source 20 may include any suitable source of hydrocarbons 22. Illustrative, non-exclusive examples of hydrocarbon sources 20 according to the present disclosure include any suitable hydrocarbon storage equipment, hydrocarbon storage tank, hydrocarbon recovery equipment, hydrocarbon deposit, oil reservoir, and/or hydrocarbon processing equipment. In the illustrative, non-exclusive example of FIG. 1, hydrocarbon source 20 may include a subsea oil well 24 that is configured to produce hydrocarbons from a hydrocarbon reservoir 26. While hydrocarbon source 20 is depicted as being beneath the surface 17 of body of water 15 in FIG. 1, it is within the scope of the present disclosure that hydrocarbon source 20 may be present at any suitable location, illustrative, non-exclusive examples of which include subsea and/or land-based locations.

Body of water 15 may include any suitable body of water in which at least a portion of hydrocarbon production system 10 extends and/or is located, such as subsea hydrocarbon pipeline 50 and/or hydrocarbon source 20. Illustrative, non-exclusive examples of body of water 15 according to the present disclosure include a lake, a river, a sea, and/or an ocean. It is within the scope of the present disclosure that at least a portion of hydrocarbon production system 10 may be located within an arctic region, or environment. When a portion of hydrocarbon production system 10 is located within an arctic region, at least a portion of a surface of the body of water may include, contain, and/or be covered by ice. Additionally or alternatively, an ambient environment proximal to at least a portion of hydrocarbon production system 10 may have a temperature of less than 10° C., less than 5° C., less than 4° C., less than 3° C., less than 2.5° C., less than 2° C., less than 1.5° C., less than 1° C., less than 0.5° C., less than 0° C., less than −0.5° C., less than −1° C., less than −1.5° C., less than −2° C., less than −2.5° C., or less than −3° C.

Hydrocarbon recovery equipment 30 may include any suitable system and/or apparatus configured to produce, transport, and/or process hydrocarbons 22. Illustrative, non-exclusive examples of hydrocarbon recovery equipment 30 according to the present disclosure include any suitable conduit, valve, pump, compressor, refinery, platform, storage tank, ship, vessel, and/or tanker. Moreover, hydrogen recovery equipment 30 may include land-based hydrocarbon recovery equipment 32 and/or water-based hydrocarbon recovery equipment 34, such as oil tanker 36 and/or oil platform 38.

As discussed in more detail herein, subsea hydrocarbon pipeline 50 may include any suitable structure that is configured to contain, transport, and/or provide a fluid conduit for a flow of hydrocarbons 22 from hydrocarbon source 20 to one or more piece(s) of hydrocarbon recovery equipment 30. As an illustrative, non-exclusive example, subsea hydrocarbon pipeline 50 may include and/or be a metallic conduit 52. It is within the scope of the present disclosure that, as discussed in more detail herein, a portion of subsea hydrocarbon pipeline 50 may, at least temporarily, include or contain one or more region(s) that may contain solids, or deposits, 54 that may obstruct, occlude, and/or block a flow of fluid 60 therethrough.

MHA 100 may be configured to inductively heat at least a selected portion 65 of subsea hydrocarbon pipeline 50. As an illustrative, non-exclusive example, MHA 100 may inductively heat an inductively coupled portion 70 of subsea hydrocarbon pipeline 50. It is within the scope of the present disclosure that MHA 100 may inductively heat only the inductively coupled portion of the subsea hydrocarbon pipeline. However, it is also within the scope of the present disclosure that MHA 100 may be configured to travel, traverse, and/or otherwise move along a length of subsea hydrocarbon pipeline 50, such as to travel, traverse, and/or otherwise move along the selected portion of the subsea hydrocarbon pipeline and thus progressively heat a plurality of inductively coupled portions 70.

The inductive heating of the subsea hydrocarbon pipeline may include the use of any suitable inductive heating element 110 to heat the inductively coupled portion of the subsea hydrocarbon pipeline. As an illustrative, non-exclusive example, inductive heating element 110 may be configured to induce an eddy current within the inductively coupled portion of the subsea hydrocarbon pipeline, such as by inducing the eddy current within a metallic portion and/or component of the subsea hydrocarbon pipeline, such as metallic conduit 52. Flow of the induced eddy current within the inductively coupled portion of the subsea hydrocarbon pipeline may produce resistive, or Joule, heating therein. References herein to the inductive heating may additionally or alternatively be referred to as induction heating and/or electromagnetic heating without departing from the scope of the present disclosure.

Inductive heating element 110 may be powered by an alternating current (AC) electric current. A frequency of the AC electric current may include any frequency suitable for inductively heating the selected portion of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of frequencies according to the present disclosure include frequencies of 1-100 kilohertz (kHz), including frequencies of 3-50 kHz, 5-30 kHz, 1-10 kHz, 10-20 kHz, or 50-100 kHz, although frequencies of less than 1 kHz, as well as frequencies of greater than 100 kHz are also within the scope of the present disclosure.

It is within the scope of the present disclosure that MHA 100 and/or inductive heating element 110 may be configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without contact between the inductive heating element and the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of contact according to the present disclosure include physical, mechanical, electrical, and/or thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.

As an illustrative, non-exclusive example, the inductive heating may include inductively heating the fluid within the subsea hydrocarbon pipeline without direct contact between the MHA 100 and subsea hydrocarbon pipeline 50. As another illustrative, non-exclusive example, the inductively heating may include physical and/or mechanical contact but not electrical and/or thermal contact between MHA 100 and subsea hydrocarbon pipeline 50. As another illustrative, non-exclusive example, and as discussed in more detail herein, it is within the scope of the present disclosure that subsea hydrocarbon pipeline 50 may include an external coating 56 that covers at least a portion of metallic conduit 52 and that the inductively heating may include intermittent, at least substantially continuous, or continuous physical and/or mechanical contact between MHA 100 and external coating 56 but not between MHA 100 and metallic conduit 52. Thus MHA 100 may be configured to inductively heat the inductively coupled portion of subsea hydrocarbon pipeline 50 through external coating 56 and/or without damage to the external coating.

Inductive heating element 110 may include any suitable structure that is configured to inductively heat and/or induce the eddy current in inductively coupled portion 70 of subsea hydrocarbon pipeline 50. As an illustrative, non-exclusive example, inductive heating element 110 my include an inductor, or coil. It is within the scope of the present disclosure that inductive heating element 110 may surround at least a portion of an outer perimeter of a cross-section of subsea hydrocarbon pipeline 50. As an illustrative, non-exclusive example, and when the subsea hydrocarbon pipeline includes an at least substantially circular cross-sectional shape, inductive heating element 110 may surround at least 10%, at least 25%, at least 50%, at least 75%, or 100% of a circumference of the cross-section of the subsea hydrocarbon pipeline. It is also within the scope of the present disclosure that inductive heating element 110 may include any suitable cross-sectional shape, illustrative, non-exclusive examples of which include any suitable arcuate, semi-circular, and/or u-shaped cross-sectional shape.

Inductively coupled portion 70 of subsea hydrocarbon pipeline 50 includes a portion of subsea hydrocarbon pipeline that is in inductive communication with inductive heating element 110 of MHA 100 at a given point in time. Additionally or alternatively, inductively coupled portion 70 may include a portion of the subsea hydrocarbon pipeline that is in sufficient inductive communication with inductive heating element 110 at a particular point in time to be heated by the inductive heating element. As an illustrative, non-exclusive example, the inductively coupled portion of the subsea hydrocarbon pipeline may include portion(s) of the subsea hydrocarbon pipeline that are in sufficient inductive communication with the inductive heating element to be heated by at least a threshold amount by the inductive heating element. Illustrative, non-exclusive examples of threshold amounts according to the present disclosure include at least 0.5° C., at least 1° C., at least 2° C., at least 3° C., at least 5° C., at least 10° C., at least 15° C., or at least 20° C.

Inductively coupled portion 70 may include any suitable portion of a length of subsea hydrocarbon pipeline 50. As an illustrative, non-exclusive example, inductively coupled portion 70 may include less than 10 meters, less than 7 meters, less than 5 meters, less than 3 meters, less than 2 meters, or less than 1 meter of the length of the subsea hydrocarbon pipeline. It is within the scope of the present disclosure that inductively coupled portion 70 may have a length that is equal to, greater than, or less than these illustrative, non-exclusive examples of lengths. Likewise, it also is within the scope of the present disclosure the inductively coupled portion 70 may have a length that is within the range set forth in these illustrative, non-exclusive examples.

As discussed in more detail herein, subsea hydrocarbon pipeline 50 may be configured to provide a fluid conduit for the flow of fluid 60 therethrough. It is within the scope of the present disclosure that MHA 100 may be configured to inductively heat the inductively coupled portion and/or the selected portion of the subsea hydrocarbon pipeline while fluid 60 is present within the subsea hydrocarbon pipeline and/or while fluid 60 is flowing through the subsea hydrocarbon pipeline. Additionally or alternatively, MHA 100 may be configured to inductively heat subsea hydrocarbon pipeline 50 without disrupting the flow of fluid 60 through subsea hydrocarbon pipeline 50.

At any given time, MHA 100 may inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline, while, over a period of time, MHA 100 may inductively heat a portion, or region, of the subsea hydrocarbon pipeline, such as the selected portion of the subsea hydrocarbon pipeline, that is larger than the inductively coupled portion. Thus, the inductively coupled portion of the subsea hydrocarbon pipeline also may be referred to as a sub-portion of the selected portion of the subsea hydrocarbon pipeline.

The selected portion of the subsea hydrocarbon pipeline may be chosen based at least in part upon a variable associated with the subsea hydrocarbon pipeline and/or a variable associated with the selected portion of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of variables according to the present disclosure include any suitable temperature and/or pressure associated with the subsea hydrocarbon pipeline and/or the selected portion thereof.

As an illustrative, non-exclusive example, the selected portion of the subsea hydrocarbon pipeline may include a portion of the subsea hydrocarbon pipeline that has a temperature that is less than a threshold temperature. Illustrative, non-exclusive examples of threshold temperatures according to the present disclosure include temperatures that are less than the WAT for fluid 60 and/or temperatures that are less than the hydrate-formation temperature for fluid 60. Additionally or alternatively, this may include temperatures that are within a threshold temperature differential of the WAT and/or the hydrate-formation temperature for fluid 60.

Further illustrative, non-exclusive examples of threshold temperatures according to the present disclosure include temperatures of less than 100° C., less than 90° C., less than 80° C., less than 75° C., less than 70° C., less than 65° C., less than 60° C., less than 55° C., less than 50° C., less than 45° C., less than 40° C., less than 35° C., less than 30° C., less than 25° C., less than 20° C., less than 15° C., or temperatures of less than 10° C. This temperature may be measured at any suitable location within the subsea hydrocarbon pipeline, illustrative, non-exclusive examples of which include on an internal surface of the subsea hydrocarbon pipeline, within the subsea hydrocarbon pipeline, on an external surface of the subsea hydrocarbon pipeline, within fluid 60 that flows through the subsea hydrocarbon pipeline, and/or within a wall of metallic conduit 52 of the subsea hydrocarbon pipeline.

As another illustrative, non-exclusive example, the selected portion of the subsea hydrocarbon pipeline may include a portion of the subsea hydrocarbon pipeline that has an internal pressure that is greater than a threshold pressure. Illustrative, non-exclusive examples of threshold pressures according to the present disclosure include pressures that are greater than the hydrate formation pressure for fluid 60 and/or pressures that are within a threshold pressure differential of the hydrate formation pressure for fluid 60.

Additionally or alternatively, it is also within the scope of the present disclosure that the selected portion of the subsea hydrocarbon pipeline may be determined based upon a model of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of models of the hydrocarbon pipeline include any suitable mathematical model, fundamental model, statistical model, thermodynamic model, kinetic model, computer model, and/or empirical model. It is within the scope of the present disclosure that the model may determine the selected portion of the subsea hydrocarbon pipeline based, at least in part, upon a prediction of the formation of an obstruction, an occlusion, a blockage, a solid, a deposit, and/or a solid deposit within an obstructed portion of the subsea hydrocarbon pipeline, and that the selected portion of the subsea hydrocarbon pipeline may be chosen such that the obstructed portion of the subsea hydrocarbon pipeline forms a sub-portion of the selected portion of the subsea hydrocarbon pipeline.

The selected portion of the subsea hydrocarbon pipeline may include any suitable proportion, or percentage, of a length of the subsea hydrocarbon pipeline. As an illustrative, non-exclusive example, the selected portion of the subsea hydrocarbon pipeline may include at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 70%, at least 90%, at least 95%, a majority of, substantially all, or all of the length of the subsea hydrocarbon pipeline. Additionally or alternatively, the subsea hydrocarbon pipeline may include any suitable overall length, illustrative, non-exclusive examples of which include overall lengths of at least 1 km, at least 5 km, at least 10 km, at least 25 km, at least 50 km, at least 75 km, at least 100 km, at least 250 km, at least 500 km, at least 1000 km, or at least 1500 km.

It is within the scope of the present disclosure that MHA 100 may utilize any suitable process, procedure, and/or method to inductively heat the selected portion of the subsea hydrocarbon pipeline. As an illustrative, non-exclusive example, MHA 100 may be configured, directed, and/or controlled to inductively heat at least a sub-portion of the selected portion of the subsea hydrocarbon pipeline continuously, intermittently, and/or with a predetermined frequency. As another illustrative, non-exclusive example, MHA 100 may be configured, directed, and/or controlled to inductively heat at least a sub-portion of the selected portion of the subsea hydrocarbon pipeline responsive to the variable associated with the subsea hydrocarbon pipeline exceeding a threshold value.

Inductively heating the selected portion of the subsea hydrocarbon pipeline may include melting an obstruction present within the selected portion of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of obstructions according to the present disclosure include a wax, a hydrate, an asphaltene, and/or scale. When the obstruction includes a wax, MHA 100 may be configured to heat the inductively coupled portion and/or the selected portion of subsea hydrocarbon pipeline 50 to a temperature of at least 50° C., at least 55° C., at least 60° C., at least 65° C., at least 70° C., at least 75° C., at least 80° C., at least 85° C., at least 90° C., at least 95° C., or at least 100° C. Additionally or alternatively, and when the obstruction includes a hydrate, MHA 100 may be configured to heat the inductively coupled portion of subsea hydrocarbon pipeline 50 to a temperature of at least 10° C., at least 15° C., at least 20° C., at least 25° C., at least 30° C., at least 35° C., at least 40° C., at least 45° C., at least 50° C., at least 55° C., at least 60° C., or at least 65° C.

FIG. 2 provides a schematic cross-sectional view of an illustrative, non-exclusive example of subsea hydrocarbon pipelines 50 that may form a portion of hydrocarbon production system 10 and/or may be utilized with the systems and methods according to the present disclosure. As discussed in more detail herein, subsea hydrocarbon pipeline 50 includes metallic conduit 52. Subsea hydrocarbon pipeline 50 is configured to provide a fluid conduit for transmission of fluid 60 and also may include one or more external coating 56 and/or internal coating 58.

Illustrative, non-exclusive examples of metallic conduits 52 according to the present disclosure include any suitable pipeline and/or oil pipeline that may include any suitable external diameter. As an illustrative, non-exclusive example, the subsea hydrocarbon pipeline may be at least 0.05 m, at least 0.1 m, at least 0.2 m, at least 0.25 m, at least 0.3 m, at least 0.5 m, at least 0.75 m, at least 1 m, at least 1.25 m, at least 1.5 m, at least 1.75 m, or at least 2 m in diameter.

Illustrative, non-exclusive examples of external coatings 56 and/or internal coatings 58 according to the present disclosure include any suitable thermal insulation, electrical insulation, corrosion-resistant coating, sheath, wrap, paint, epoxy, resin, and/or polymer. These coatings may be constructed of any suitable material.

Illustrative, non-exclusive examples of fluid 60 include any suitable hydrocarbon, oil, crude oil, natural gas, aromatic hydrocarbons, alkanes, alkenes, alkynes, and/or water. As discussed in more detail herein, fluid 60 also may include wax, asphaltenes, and/or resins, a portion of which may solidify, precipitate, separate, and/or otherwise phase-separate from the bulk of the fluid to produce a solid, solid-like, gel, and/or gel-like precipitate 72 and/or solids deposit 54 that may form a portion of an obstruction 76 to a flow of fluid 60 through subsea hydrocarbon pipeline 50. Illustrative, non-exclusive examples of components of obstruction 76 may include wax 78, hydrates 80, asphaltenes 82, and/or scale 84.

FIG. 3 provides a schematic representation of an illustrative, non-exclusive example of hydrocarbon production system 10, including MHA 100 according to the present disclosure. As discussed in more detail herein, MHA 100 includes inductive heating element 110 and may be configured to inductively heat selected portion 65 of subsea hydrocarbon pipeline 50. This may include inductively heating inductively coupled portion 70 of the subsea hydrocarbon pipeline at a given time and traversing selected portion 65 of the subsea hydrocarbon pipeline to inductively heat the entire selected portion of the subsea hydrocarbon pipeline over a period of time.

MHA 100 may be operatively attached to and/or form a portion of a mobile subsea conveyance 117, such as a remotely operated vehicle (ROV) 120, that may include a propulsion mechanism 125 that is configured to convey the MHA along the selected portion of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of propulsion mechanisms 125 according to the present disclosure include any suitable propeller, turbine, motor, magnet, and/or electromagnet.

MHA 100 also may include and/or be in wired and/or wireless communication with a controller 130 that is configured to control the operation of at least a portion of MHA 100. It is within the scope of the present disclosure that controller 130 may be configured to control a supply of electrical energy to inductive heating element 110, a supply of electrical energy to propulsion mechanism 125, a speed of MHA 100 as it traverses the selected portion of subsea hydrocarbon pipeline 50, a temperature of a portion of subsea hydrocarbon pipeline 50, a location of MHA 100 with respect to subsea hydrocarbon pipeline 50 and/or selected portion 65 of the subsea hydrocarbon pipeline 50, and/or a portion of subsea hydrocarbon pipeline 50 that forms selected portion 65. Controller 130 may utilize manual and/or automatic control.

As an illustrative, non-exclusive example, controller 130 may be configured to detect a local temperature of subsea hydrocarbon pipeline 50 and/or inductively coupled portion 70 thereof and may control a speed at which MHA 100 traverses selected portion 65 based thereon. This may include increasing the speed responsive to the local temperature being greater than a desired, or threshold, value, and/or decreasing the speed responsive to the local temperature being less than the desired value. Increasing and/or decreasing the speed may, additionally or alternatively, include controlling a flow of electric current to propulsion mechanism 125.

As another illustrative, non-exclusive example, controller 130 may be configured to detect the local temperature and may control an electric current that is supplied to inductive heating element 110 based thereon. This may include increasing the electric current responsive to the local temperature being less than the desired value, and/or decreasing the electric current responsive to the local temperature being greater than the desired value.

As yet another illustrative, non-exclusive example, controller 130 may be configured to determine selected portion 65 of subsea hydrocarbon pipeline 50 and to control a location of MHA 100 on and/or with respect to the subsea hydrocarbon pipeline based thereon. This may include determining selected portion 65 using any suitable variable associated with the subsea hydrocarbon pipeline and/or model of the subsea hydrocarbon pipeline as discussed in more detail herein.

MHA 100 also may include and/or be in electrical communication with one or more power sources 140 that are configured to provide power to MHA 100, such as to inductive heating element 110, remotely operated vehicle 120, propulsion mechanism 125, and/or controller 130 thereof. Power source 140 may form a portion of, be operatively attached to, and/or be housed on MHA 100. Additionally or alternatively, power source 140 may be separate from, but in electrical communication with, MHA 100. Illustrative, non-exclusive examples of power sources 140 according to the present disclosure include any suitable ship-based power source, electrical generator, and/or electrical grid.

Electric current from power source 140 may be supplied to MHA 100 using any suitable electric conduit 145. As an illustrative, non-exclusive example, electric conduit 145 may include a separate, or dedicated, electric conduit, such as an electric cable and/or wire. As another illustrative, non-exclusive example, electric conduit 145 may, additionally or alternatively, include subsea hydrocarbon pipeline 50. When electric conduit 145 includes subsea hydrocarbon pipeline 50, it is within the scope of the present disclosure that the subsea hydrocarbon pipeline may provide electric power to MHA 100 through inductive coupling between the subsea hydrocarbon pipeline and the MHA.

FIG. 4 provides a less schematic but still illustrative, non-exclusive example of hydrocarbon production system 10, including MHA 100, according to the present disclosure. In FIG. 4, at least a portion of subsea hydrocarbon pipeline 50 is located beneath the surface 17 of body of water 15 and inductively coupled portion 70 of subsea hydrocarbon pipeline 50 is heated by inductive heating element 110 of MHA 100. MHA 100 may be operatively attached to and/or form a portion of ROV 120, which includes propulsion mechanism 125, such as a propeller 127. Electrical conduit 145 provides electrical communication between MHA 100 and water-based hydrocarbon recovery equipment 34.

Water-based hydrocarbon recovery equipment 34 may be or include a ship 35 and may include or contain controller 130 and power source 140. Controller 130 may include a surface-based controller 132, which may communicate with MHA 100 through communication linkage 147 of electric conduit 145. Power source 140 may include a surface-based power source 142, such as a generator 144, and may provide electrical power to MHA 100 through power supply conduit 149 of electric conduit 145.

FIG. 5 provides a schematic cross-sectional view of another illustrative, non-exclusive example of hydrocarbon production system 10, including MHA 100, according to the present disclosure. In FIG. 5, MHA 100 includes inductive heating element 110, which may be operatively attached to and/or form a portion of ROV 120. Inductive heating element 110 surrounds at least a portion of subsea hydrocarbon pipeline 50. As shown in dashed lines in FIG. 5, it is within the scope of the present disclosure that, as discussed in more detail herein, inductive heating element 110 may extend around, encompass, and/or otherwise surround any suitable portion of subsea hydrocarbon pipeline 50 and may include any suitable cross-sectional shape, including arcuate shapes, semi-circular shapes, u-shapes, and/or shapes that may be similar and/or complementary to the cross-sectional shape of subsea hydrocarbon pipeline 50.

As also shown in dashed lines in FIG. 5, MHA 100 optionally also may include one or more guide structure(s) 115 that are configured to guide, direct, constrain, and/or otherwise locate inductive heating element 110 with respect to subsea hydrocarbon pipeline 50. Guide structures 115 may include any suitable structure that is configured to at least temporarily contact the subsea hydrocarbon pipeline without damage to the subsea hydrocarbon pipeline and/or that is configured to maintain a spaced-apart relationship between inductive heating element 110 and subsea hydrocarbon pipeline 50. Illustrative, non-exclusive examples of guide structures 115 according to the present disclosure include any suitable roller, bumper, bearing, pad, and/or blunt surface.

FIG. 6 provides illustrative, non-exclusive examples of methods 200 according to the present disclosure of removing an obstruction from a subsea hydrocarbon pipeline. As shown in dashed lines in FIG. 6, the methods optionally may include determining a location of a solids deposit (or other occlusion) within a subsea hydrocarbon pipeline at 205 and moving an MHA into inductive communication with the subsea hydrocarbon pipeline at 210. The methods include inductively heating an initial, or inductively coupled, portion of the subsea hydrocarbon pipeline at 215 and optionally may include inductively heating through thermal insulation at 220 and/or inductively heating without contact between the inductive heating element and the subsea hydrocarbon pipeline at 225. The methods further optionally may include transferring thermal energy from the subsea hydrocarbon pipeline to an obstruction at 230, melting a portion of the obstruction at 235, injecting an obstruction-dissolving compound into the subsea hydrocarbon pipeline at 240, traversing a selected portion of the subsea hydrocarbon pipeline with the MHA at 245, and/or inductively heating a subsequent portion of the subsea hydrocarbon pipeline at 250.

Determining the location of a solids deposit at 205 may include the use of any suitable detector, model, and/or algorithm to determine the location of the solids deposit. As an illustrative, non-exclusive example, and as discussed in more detail herein with reference to determining the selected portion of the subsea hydrocarbon pipeline, this may include determining and/or predicting the location of the solids deposit based at least in part on a variable associated with the subsea hydrocarbon pipeline. As another illustrative, non-exclusive example, and as also discussed in more detail herein with reference to determining the selected portion of the subsea hydrocarbon pipeline, this also may include the use of any suitable model to determine and/or predict the location of the solids deposit.

Moving the MHA into inductive communication with the subsea hydrocarbon pipeline at 210 may include moving the MHA into inductive communication with an inductively coupled portion of the subsea hydrocarbon pipeline. It is within the scope of the present disclosure that, prior to moving the MHA into inductive communication with the subsea hydrocarbon pipeline at 210, the MHA may not have been in inductive communication with the subsea hydrocarbon pipeline. Additionally or alternatively, it is also within the scope of the present disclosure that the moving includes moving the MHA from inductive communication with a first, or previously inductively coupled, portion of the subsea hydrocarbon pipeline and into inductive communication with a second, or subsequently inductively coupled, portion of the subsea hydrocarbon pipeline, such as a portion of the subsea hydrocarbon pipeline that includes, is expected to include, is predicted to include, and/or is proximal to the obstruction.

It is within the scope of the present disclosure that the moving also may include maintaining a spaced-apart relationship between at least a portion of the MHA and at least a portion of the subsea hydrocarbon pipeline. As an illustrative, non-exclusive example, and as discussed in more detail herein, this may include maintaining a spaced-apart relationship between the inductive heating element of the MHA and the subsea hydrocarbon pipeline. As another illustrative, non-exclusive example, and as also discussed in more detail herein, this also may include the use of one or more guide structures to maintain the spaced-apart relationship.

Inductively heating the initial portion of the subsea hydrocarbon pipeline at 215 may include inducing an eddy current within a metallic component of the inductively coupled portion of the subsea hydrocarbon pipeline and producing heat within the metallic component. As discussed in more detail herein, the subsea hydrocarbon pipeline may be configured to provide for a flow of a fluid therethrough. It is within the scope of the present disclosure that the inductively heating may include inductively heating concurrently with and/or without disrupting a flow of fluid through the subsea hydrocarbon pipeline.

Inductively heating the subsea hydrocarbon pipeline through thermal insulation at 220 may include inductively heating the subsea hydrocarbon pipeline without damaging, compromising, and/or removing the thermal insulation. Additionally or alternatively, the inductively heating through thermal insulation also may include inductively heating through any other suitable external coating of the subsea hydrocarbon pipeline and/or through a material that may separate or otherwise be located between the inductive heating coil and the metallic component of the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of coatings and/or materials that may separate the indicative heating coil from the metallic component of the subsea hydrocarbon pipeline include electrical insulation, corrosion-resistant coatings, and/or water. As discussed in more detail herein, inductively heating without contact between the inductive heating element and the subsea hydrocarbon pipeline at 225 may include inductively heating without physical, mechanical, electrical, and/or thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.

Transferring thermal energy from the subsea hydrocarbon pipeline to the obstruction at 230 may include conducting, convecting, and/or radiating thermal energy from the inductively coupled portion of the subsea hydrocarbon pipeline to the obstruction to heat the obstruction. This transferring also may include melting at least a portion of the obstruction at 235.

It is within the scope of the present disclosure that the melting may include softening the obstruction, causing at least a portion of the obstruction to undergo a phase transition, supplying a heat of fusion to at least a portion of the obstruction, liquefying at least a portion of the obstruction, supplying a heat of vaporization to at least a portion of the obstruction, vaporizing at least a portion of the obstruction, decreasing a viscosity of at least a portion of the obstruction, decreasing a rigidity of at least a portion of the obstruction, decreasing an adhesion between an inner wall of the subsea hydrocarbon pipeline and at least a portion of the obstruction, and/or detaching at least a portion of the obstruction from the inner wall of the subsea hydrocarbon pipeline. This may include melting any suitable portion of the obstruction, illustrative, non-exclusive examples of which include the entire obstruction, a portion of the obstruction that is in fluid communication with the fluid that flows through the subsea hydrocarbon pipeline, and/or a portion of the obstruction that is proximal to the inner wall of the subsea hydrocarbon pipeline.

The obstruction may include any suitable chemical composition, including the illustrative, non-exclusive examples of obstructions discussed in more detail herein. The melting may include heating the obstruction and/or any suitable portion of the subsea hydrocarbon pipeline to any suitable temperature, including the illustrative, non-exclusive examples of heating temperatures discussed in more detail herein.

Injecting the obstruction-dissolving compound into the subsea hydrocarbon pipeline at 240 may include injecting the obstruction-dissolving compound into the fluid that flows through the subsea hydrocarbon pipeline. Illustrative, non-exclusive examples of obstruction-dissolving compounds according to the present disclosure include methanol, ethylene glycol, a kinetic inhibitor, and/or an anti-agglomerate and are discussed in more detail herein.

It is within the scope of the present disclosure that, prior to the inductively heating at 215, fluid flow through the subsea hydrocarbon pipeline may be blocked, prevented, slowed, and/or otherwise occluded by the presence of the obstruction within the subsea hydrocarbon pipeline. Thus, the inductively heating may include increasing and/or establishing the fluid flow within the subsea hydrocarbon pipeline by removing at least a portion of the obstruction from the subsea hydrocarbon pipeline and the injecting may include injecting subsequent to increasing and/or establishing the fluid flow. As an illustrative, non-exclusive example, the obstruction may at least substantially block fluid flow within the subsea hydrocarbon pipeline, thereby decreasing and/or preventing a delivery of the obstruction-dissolving compound into fluid and/or chemical communication with the obstruction. Under these conditions, the inductively heating may increase and/or establish the fluid flow, thereby providing for more effective delivery of the obstruction-dissolving compound to the obstruction.

Traversing the selected portion of the subsea hydrocarbon pipeline with the MHA at 245 may include moving the MHA along a length of the subsea hydrocarbon pipeline to melt and/or prevent the formation of obstructions therein. As discussed in more detail herein, the MHA may, at a given time, inductively heat a first, or initially inductively coupled, portion of the subsea hydrocarbon pipeline; however, over a period of time, the MHA may inductively heat the selected portion of the subsea hydrocarbon pipeline, wherein the selected portion is larger than but includes the first portion. This may be accomplished by traversing, or traveling along, at least a portion of the length of the subsea hydrocarbon pipeline with the MHA to heat at least a second, or subsequently inductively coupled, portion of the subsea hydrocarbon pipeline that is different from the first portion as shown at 250. Illustrative, non-exclusive examples of the selected portion of the subsea hydrocarbon pipeline and/or the portion of the subsea hydrocarbon pipeline that may be traversed by the MHA are discussed in more detail herein.

In the present disclosure, several of the illustrative, non-exclusive examples have been discussed and/or presented in the context of flow diagrams, or flow charts, in which the methods are shown and described as a series of blocks, or steps. Unless specifically set forth in the accompanying description, it is within the scope of the present disclosure that the order of the blocks may vary from the illustrated order in the flow diagram, including with two or more of the blocks (or steps) occurring in a different order and/or concurrently. It is also within the scope of the present disclosure that the blocks, or steps, may be implemented as logic, which also may be described as implementing the blocks, or steps, as logics. In some applications, the blocks, or steps, may represent expressions and/or actions to be performed by functionally equivalent circuits or other logic devices. The illustrated blocks may, but are not required to, represent executable instructions that cause a computer, processor, and/or other logic device to respond, to perform an action, to change states, to generate an output or display, and/or to make decisions.

As used herein, the term “and/or” placed between a first entity and a second entity means one of (1) the first entity, (2) the second entity, and (3) the first entity and the second entity. Multiple entities listed with “and/or” should be construed in the same manner, i.e., “one or more” of the entities so conjoined. Other entities may optionally be present other than the entities specifically identified by the “and/or” clause, whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, a reference to “A and/or B,” when used in conjunction with open-ended language such as “comprising” may refer, in one embodiment, to A only (optionally including entities other than B); in another embodiment, to B only (optionally including entities other than A); in yet another embodiment, to both A and B (optionally including other entities). These entities may refer to elements, actions, structures, steps, operations, values, and the like.

As used herein, the phrase “at least one,” in reference to a list of one or more entities should be understood to mean at least one entity selected from any one or more of the entity in the list of entities, but not necessarily including at least one of each and every entity specifically listed within the list of entities and not excluding any combinations of entities in the list of entities. This definition also allows that entities may optionally be present other than the entities specifically identified within the list of entities to which the phrase “at least one” refers, whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) may refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including entities other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including entities other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other entities). In other words, the phrases “at least one,” “one or more,” and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C” and “A, B, and/or C” may mean A alone, B alone, C alone, A and B together, A and C together, B and C together, A, B and C together, and optionally any of the above in combination with at least one other entity.

In the event that any of the references that are incorporated by reference herein define a term in a manner or are otherwise inconsistent with either the non-incorporated portion of the present disclosure or with any of the other incorporated references, the non-incorporated portion of the present disclosure shall control, and the term or incorporated disclosure therein shall only control with respect to the reference in which the term is defined and/or the incorporated disclosure was originally present.

As used herein the terms “adapted” and “configured” mean that the element, component, or other subject matter is designed and/or intended to perform a given function. Thus, the use of the terms “adapted” and “configured” should not be construed to mean that a given element, component, or other subject matter is simply “capable of” performing a given function but that the element, component, and/or other subject matter is specifically selected, created, implemented, utilized, and/or designed for the purpose of performing the function. It is also within the scope of the present disclosure that elements, components, and/or other recited subject matter that is recited as being adapted to perform a particular function may additionally or alternatively be described as being configured to perform that function, and vice versa.

Illustrative, non-exclusive examples of systems and methods according to the present disclosure are presented in the following enumerated paragraphs. It is within the scope of the present disclosure that an individual step of a method recited herein, including in the following enumerated paragraphs, may additionally or alternatively be referred to as a “step for” performing the recited action.

A1. A mobile subsea hydrocarbon pipeline heating assembly, comprising:

means for inductively heating an inductively coupled portion of a subsea hydrocarbon pipeline; and

means for moving the means for inductively heating along at least a selected portion of the subsea hydrocarbon pipeline.

A2. The assembly of paragraph A1, wherein the means for inductively heating includes an inductive heating element.

A3. The assembly of any of paragraphs A1-A2, wherein the means for moving includes a mobile subsea conveyance configured to traverse at least the selected portion of the subsea hydrocarbon pipeline.

A4. The assembly of paragraph A3, wherein the mobile subsea conveyance is operatively attached to the means for inductively heating.

B1. A mobile subsea hydrocarbon pipeline heating assembly, comprising:

a mobile subsea conveyance configured to traverse at least a selected portion of a subsea hydrocarbon pipeline; and

an inductive heating element that is operatively attached to the mobile subsea conveyance and configured to inductively heat an inductively coupled portion of the subsea hydrocarbon pipeline.

C1. The assembly of any of paragraphs A3-B1, wherein the mobile subsea conveyance includes a remotely operated vehicle.

C2. The assembly of any of paragraphs A3-C1, wherein the mobile subsea conveyance includes a propulsion mechanism, and optionally wherein the propulsion mechanism includes at least one of a propeller, a turbine, a motor, and a magnet.

C3. The assembly of any of paragraphs A2-C2, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that is in inductive communication with the inductive heating element, and optionally wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that is in sufficient inductive communication with the inductive heating element to be heated by the inductive heating element.

C4. The assembly of any of paragraphs A1-C3, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes less than 10 meters of a length of the subsea hydrocarbon pipeline, optionally including less than 7 meters, less than 5 meters, less than 3 meters, less than 2 meters, or less than 1 meter of the length of the subsea hydrocarbon pipeline.

C5. The assembly of any of paragraphs A1-C4, wherein, at a given time, the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline.

C6. The assembly of paragraph C5, wherein the given time includes a first given time and the inductively coupled portion includes a first inductively coupled portion, and further wherein, subsequent to inductively heating the first inductively coupled portion of the subsea hydrocarbon pipeline at the first given time, the mobile subsea hydrocarbon pipeline heating assembly is further configured to inductively heat a second inductively coupled portion of the subsea hydrocarbon pipeline at a second given time, wherein the first inductively coupled portion is different from the second inductively coupled portion.

C7. The assembly of any of paragraphs A1-C6, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a sub-portion of the selected portion of the subsea hydrocarbon pipeline.

C8. The assembly of paragraph C7, wherein the selected portion of the subsea hydrocarbon pipeline is determined based upon a variable associated with the selected portion of the subsea hydrocarbon pipeline.

C9. The assembly of paragraph C8, wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.

C10. The assembly of paragraph C9, wherein the selected portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that includes a pipeline temperature that is less than a threshold temperature.

C11. The assembly of paragraph C10, wherein the pipeline temperature is measured in at least one of an internal surface of the subsea hydrocarbon pipeline, an external surface of the subsea hydrocarbon pipeline, a fluid that flows through the subsea hydrocarbon pipeline, and within a wall of a metallic conduit that comprises the subsea hydrocarbon pipeline.

C12. The assembly of any of paragraphs C10-C11, wherein the threshold temperature includes a temperature of less than 100° C., optionally including threshold temperatures of less than 90° C., less than 80° C., less than 75° C., less than 70° C., less than 65° C., less than 60° C., less than 55° C., less than 50° C., less than 45° C., less than 40° C., less than 35° C., less than 30° C., less than 25° C., less than 20° C., less than 15° C., or less than 10° C.

C13. The assembly of any of paragraphs C9-C12, wherein the selected portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that includes an internal pressure that is greater than a threshold pressure.

C14. The assembly of any of paragraphs C7-C13, wherein the selected portion of the subsea hydrocarbon pipeline is determined based upon a model of the subsea hydrocarbon pipeline, and optionally wherein the model includes at least one of a mathematical model, a computer model, and an empirical model.

C15. The assembly of paragraph C14, wherein the model is configured to predict the formation of at least one of an obstruction, an occlusion, a solid, a deposit, and a solid deposit within an obstructed portion of the subsea hydrocarbon pipeline, and further wherein the selected portion of the subsea hydrocarbon pipeline includes the obstructed portion of the subsea hydrocarbon pipeline.

C16. The assembly of any of paragraphs C7-C15, wherein the selected portion of the subsea hydrocarbon pipeline includes at least 10% of a length of the subsea hydrocarbon pipeline, optionally including at least 20%, at least 30%, at least 40%, at least 50%, at least 70%, at least 90%, at least 95%, a majority of, substantially all, or all of the length of the subsea hydrocarbon pipeline.

C17. The assembly of paragraph C16, wherein the length of the subsea hydrocarbon pipeline is at least 1 km, optionally including lengths of at least 5 km, at least 10 km, at least 25 km, at least 50 km, at least 75 km, at least 100 km, at least 250 km, at least 500 km, at least 1000 km, or at least 1500 km.

C18. The assembly of any of paragraphs C7-C17, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat at least a sub-portion of the selected portion of the subsea hydrocarbon pipeline continuously.

C19. The assembly of any of paragraphs C7-C18, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat at least a sub-portion of the selected portion of the subsea hydrocarbon pipeline intermittently.

C20. The assembly of paragraph C18, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat a given sub-portion of the selected portion of the subsea hydrocarbon pipeline with a predetermined frequency.

C21. The assembly of any of paragraphs C19-C20, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat a given sub-portion of the selected portion of the subsea hydrocarbon pipeline responsive to a variable associated with the subsea hydrocarbon pipeline exceeding a threshold value.

C22. The assembly of any of paragraphs A1-C21, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline to melt an obstruction present within the subsea hydrocarbon pipeline.

C23. The assembly of paragraph C22, wherein the obstruction includes at least one of a wax, a hydrate, an asphaltene, and scale.

C24. The assembly of paragraph C23, wherein the obstruction includes a wax and the assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline to a pipeline temperature of at least 50° C., optionally including pipeline temperatures of at least 55° C., 60° C., 65° C., 70° C., 75° C., 80° C., 85° C., 90° C., 95° C., or 100° C.

C25. The assembly of paragraph C23, wherein the obstruction includes a hydrate and the assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline to a pipeline temperature of at least 10° C., optionally including temperatures of at least 15° C., 20° C., 25° C., 30° C., 35° C., 40° C., 45° C., 50° C., 55° C., 60° C., or 65° C.

C26. The assembly of any of paragraphs C24-C25, wherein the pipeline temperature includes a temperature of at least one of an internal surface of the subsea hydrocarbon pipeline, an external surface of the subsea hydrocarbon pipeline, and a wall of a metallic conduit that comprises the subsea hydrocarbon pipeline.

C27. The assembly of any of paragraphs A1-C26, wherein the mobile subsea hydrocarbon pipeline heating assembly is in communication with a controller configured to control the operation of the mobile subsea hydrocarbon pipeline heating assembly, and optionally wherein the mobile subsea hydrocarbon pipeline heating assembly includes the controller.

C28. The assembly of paragraph C27, wherein the controller includes at least one of an automatic controller and a manual controller.

C29. The assembly of any of paragraphs C27-C28, wherein the controller forms a part of the mobile subsea hydrocarbon pipeline heating assembly.

C30. The assembly of any of paragraphs C27-C28, wherein the controller is separate from the mobile subsea hydrocarbon pipeline heating assembly.

C31. The assembly of paragraph C30, wherein the controller is configured to communicate with the mobile subsea hydrocarbon pipeline heating assembly using at least one of a wired communication linkage and a wireless communication linkage.

C32. The assembly of any of paragraphs C27-C31, wherein the controller is configured to detect a variable associated with the subsea hydrocarbon pipeline and to control the operation of the mobile subsea hydrocarbon pipeline heating assembly responsive at least in part thereto.

C33. The assembly of paragraph C32, wherein the variable associated with the subsea hydrocarbon pipeline includes at least one of a temperature associated with the subsea hydrocarbon pipeline and a pressure associated with the subsea hydrocarbon pipeline.

C34. The assembly of any of paragraphs C32-C33, wherein the controller is configured to control at least one of a speed of the mobile subsea conveyance as it traverses the subsea hydrocarbon pipeline, a location of the mobile subsea conveyance on the subsea hydrocarbon pipeline, and an electrical power supplied to the inductive heating element responsive to the variable associated with the subsea hydrocarbon pipeline.

C35. The assembly of any of paragraphs A2-C34, wherein the inductive heating element is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline by inducing an eddy current within a metallic portion of the subsea hydrocarbon pipeline.

C36. The assembly of paragraph C35, wherein the metallic portion of the subsea hydrocarbon pipeline includes a metallic conduit that comprises the subsea hydrocarbon pipeline.

C37. The assembly of any of paragraphs A2-C36, wherein the inductive heating element is powered by an AC electric current, and optionally wherein the AC electric current includes a frequency of 1-100 kHz, further optionally including AC electric current frequencies of 3-50 kHz, 5-30 kHz, 1-10 kHz, 10-20 kHz, or 50-100 kHz.

C38. The assembly of any of paragraphs A2-C37, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without at least one of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline, and optionally without at least two of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline, and further optionally without at least three of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.

C39. The assembly of any of paragraphs A2-C38, wherein the inductive heating element surrounds at least a portion of a circumference of the subsea hydrocarbon pipeline, and optionally wherein the portion of the circumference of the subsea hydrocarbon pipeline includes at least 10%, at least 25%, at least 50%, at least 75%, or 100% of the circumference of the subsea hydrocarbon pipeline.

C40. The assembly of any of paragraphs A2-C39, wherein at least a portion of the inductive heating element includes at least one of an arcuate, a semi-circular, and a u-shaped cross-sectional shape.

C41. The assembly of any of paragraphs A1-C40, wherein the mobile subsea hydrocarbon pipeline heating assembly further includes at least one guide structure configured to contact the subsea hydrocarbon pipeline.

C42. The assembly of paragraph C41 when depending from any of paragraphs A2-C40, wherein the at least one guide structure is configured to maintain the inductive heating element and the subsea hydrocarbon pipeline in a spaced-apart relationship.

C43. The assembly of any of paragraphs A1-C42, wherein the mobile subsea hydrocarbon pipepline heating assembly is in electrical communication with a power source configured to provide electrical current to the mobile subsea hydrocarbon pipeline heating assembly, and optionally wherein the mobile subsea hydrocarbon pipeline heating assembly includes the power source.

C44. The assembly of paragraph C43, wherein the power source at least one of forms a portion of, is operatively attached to, and is in electrical communication with at least one of the mobile subsea conveyance and the inductive heating element.

C45. The assembly of any of paragraphs C43-C44, wherein the power source provides electrical current to the mobile subsea hydrocarbon pipeline heating assembly through at least one of an electrical conduit and an inductive coupling.

C46. The assembly of any of paragraphs C43-C45, wherein the power source includes at least one of a ship-based power source, an electrical generator, and an electrical grid.

C47. The assembly of any of paragraphs A1-C46, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline while the fluid stream is flowing through the subsea hydrocarbon pipeline.

C48. The assembly of any of paragraphs A1-C47, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without disrupting a flow of a fluid through the subsea hydrocarbon pipeline.

C49. The assembly of any of paragraphs C47-C48, wherein the fluid includes at least one of a hydrocarbon, oil, and natural gas.

C50. The assembly of any of claims C1-C49, wherein the subsea hydrocarbon pipeline includes a metallic conduit, and optionally wherein the metallic conduit includes an oil pipe.

C51. The assembly of any of paragraphs C1-050, wherein the subsea hydrocarbon pipeline includes at least one of an external coating and an internal coating.

C52. The assembly of paragraph C51, wherein at least one of the external coating and the internal coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.

C53. The assembly of any of paragraphs A1-C52, wherein the subsea hydrocarbon pipeline is configured to provide a fluid connection between subsea hydrocarbon recovery equipment and at least one of hydrocarbon recovery equipment, hydrocarbon processing equipment, and hydrocarbon storage equipment that is located on at least one of land, an oil platform, a drilling rig, a ship, and an oil tanker.

C54. The assembly of paragraph C53, wherein the subsea hydrocarbon recovery equipment includes at least one of a hydrocarbon well, an oil well, a natural gas well, a pump, and a compressor.

C55. The assembly of any of paragraphs A1-054, wherein the subsea hydrocarbon pipeline includes an external diameter of at least 0.05 m, optionally including external diameters of at least 0.1 m, 0.2 m, 0.25 m, 0.5 m, 0.75 m, 1 m, 1.25 m, 1.5 m, 1.75 m, or 2 m.

D1. A method of removing an obstruction from a subsea hydrocarbon pipeline, the method comprising:

moving the mobile subsea hydrocarbon pipeline heating assembly of any of paragraphs A1-C55 into inductive communication with an inductively coupled portion of the subsea hydrocarbon pipeline; and

inductively heating the inductively coupled portion of the subsea hydrocarbon pipeline.

E1. A method of removing an obstruction from a subsea hydrocarbon pipeline, the method comprising:

inductively heating an inductively coupled portion of the subsea hydrocarbon pipeline with a mobile subsea hydrocarbon pipeline heating assembly.

F1. The method of paragraph E1, wherein prior to the inductively heating, the method includes moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the inductively coupled portion of the subsea hydrocarbon pipeline.

F2. The method of any of paragraphs D1-F1, wherein the moving includes moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the subsea hydrocarbon pipeline, and optionally wherein, prior to the moving, the mobile subsea hydrocarbon pipeline heating assembly is not in inductive communication with the subsea hydrocarbon pipeline.

F3. The method of any of paragraphs D1-F2, wherein the moving includes moving the mobile subsea hydrocarbon pipeline heating assembly from inductive communication with a previously inductively coupled portion of the subsea hydrocarbon pipeline and into inductive communication with a subsequently inductively coupled portion of the subsea hydrocarbon pipeline.

F4. The method of any of paragraphs D1-F3, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes an initially inductively coupled portion of the subsea hydrocarbon pipeline and the method further includes inductively heating a subsequently inductively coupled portion of the subsea hydrocarbon pipeline with the mobile subsea hydrocarbon pipeline heating assembly, wherein the initially inductively coupled portion is different from the subsequently inductively coupled portion.

F5. The method of any of paragraphs D1-F4, wherein the method further includes traversing at least a portion of a length of the subsea hydrocarbon pipeline and the inductively heating includes inductively heating the portion of the length of the subsea hydrocarbon pipeline.

F6. The method of paragraph F5, wherein the portion of the length of the subsea hydrocarbon pipeline includes at least 10% of the length of the subsea hydrocarbon pipeline, optionally including at least 20%, at least 30%, at least 40%, at least 50%, at least 70%, at least 90%, at least 95%, a majority of, or substantially all of, the length of the subsea hydrocarbon pipeline.

F7. The method of any of paragraphs F5-F6, wherein the length of the subsea hydrocarbon pipeline is at least 1 km, optionally including lengths of at least 5 km, at least 10 km, at least 25 km, at least 50 km, at least 75 km, at least 100 km, at least 250 km, at least 500 km, at least 1000 km, or at least 1500 km.

F8. The method of any of paragraphs D1-F7, wherein the subsea hydrocarbon pipeline includes an external coating and the inductively heating includes inductively heating through the external coating without damage to the external coating.

F9. The method of paragraph F8, wherein the external coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.

F10. The method of any of paragraphs D1-F9, wherein the inductively heating includes inductively heating without at least one of physical, mechanical, electrical, and thermal contact between an inductive heating element configured to provide the inductive heating and the subsea hydrocarbon pipeline, optionally without at least two of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline, and further optionally without at least three of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.

F11. The method of any of paragraphs D1-F10, wherein the inductively heating includes inducing an eddy current within the inductively coupled portion of the subsea hydrocarbon pipeline.

F12. The method of any of paragraphs D1-F11, wherein the method further includes determining a selected portion of the subsea hydrocarbon pipeline to be inductively heated, wherein the inductively coupled portion forms a subset of the selected portion.

F13. The method of paragraph F12, wherein the determining includes determining based at least in part on a variable associated with the selected portion of the subsea hydrocarbon pipeline.

F14. The method of paragraph F13, wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.

F15. The method of paragraph F14, wherein the selected portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that includes a pipeline temperature that is less than a threshold temperature.

F16. The method of paragraph F15, wherein the threshold temperature includes a temperature of less than 100° C., optionally including threshold temperatures of less than 90° C., less than 80° C., less than 75° C., less than 70° C., less than 65° C., less than 60° C., less than 55° C., less than 50° C., less than 45° C., less than 40° C., less than 35° C., less than 30° C., less than 25° C., less than 20° C., less than 15° C., or less than 10° C.

F17. The method of any of paragraphs F14-F16, wherein the selected portion of the subsea hydrocarbon pipeline includes a portion of the subsea hydrocarbon pipeline that includes an internal pressure that is greater than a threshold pressure.

F18. The method of any of paragraphs F12-F17, wherein the determining includes determining based at least in part on mathematical modeling of the subsea hydrocarbon pipeline.

F19. The method of paragraph F18, wherein the mathematical modeling includes predicting the formation of at least one of an obstruction, an occlusion, a solid, a deposit, and a solid deposit within an obstructed portion of the subsea hydrocarbon pipeline, and further wherein the selected portion of the subsea hydrocarbon pipeline includes the obstructed portion of the subsea hydrocarbon pipeline.

F20. The method of any of paragraphs D1-F19, wherein the method further includes transferring thermal energy from the subsea hydrocarbon pipeline to the obstruction.

F21. The method of paragraph F20, wherein the transferring includes melting at least a portion of the obstruction, and optionally wherein the obstruction includes at least one of a wax, a hydrate, an asphaltene, and scale.

F22. The method of paragraph F21, wherein the obstruction includes a wax and the inductively heating includes inductively heating the inductively coupled portion of the subsea hydrocarbon pipeline to a pipeline temperature of at least 50° C., optionally including pipeline temperatures of at least 55° C., 60° C., 65° C., 70° C., 75° C., 80° C., 85° C., 90° C., 95° C., or 100° C.

F23. The method of paragraph F21, wherein the obstruction includes a hydrate and the assembly is configured to inductively heat the selected portion of the subsea hydrocarbon pipeline to a pipeline temperature of at least 10° C., optionally including pipeline temperatures of at least 15° C., 20° C., 25° C., 30° C., 35° C., 40° C., 45° C., 50° C., 55° C., 60° C., or 65° C.

F24. The method of any of paragraphs F22-F23, wherein the pipeline temperature includes a temperature of at least one of an internal surface of the subsea hydrocarbon pipeline, an external surface of the subsea hydrocarbon pipeline, and a wall of a metallic conduit that comprises the subsea hydrocarbon pipeline.

F25. The method of any of paragraphs F21-F24, wherein melting at least a portion of the obstruction includes melting a portion of the obstruction that is proximal an internal wall of the subsea hydrocarbon pipeline.

F26. The method of any of paragraphs D1-F25, wherein the method further includes determining a location of an obstructed portion of the subsea hydrocarbon pipeline, wherein the obstructed portion includes the obstruction, and further wherein moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the inductively coupled portion of the subsea hydrocarbon pipeline includes moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the obstructed portion of the subsea hydrocarbon pipeline.

F27. The method of any of paragraphs D1-F26, wherein the method further includes maintaining a spaced-apart relationship between the subsea hydrocarbon pipeline and an inductive heating element that is configured to provide the inductive heating.

F28. The method of any of paragraphs D1-F27, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the method includes flowing the fluid stream through the fluid conduit concurrently with the inductively heating.

F29. The method of paragraph F28, wherein the inductively heating includes inductively heating without disrupting the flowing.

F30. The method of any of paragraphs D1-F29, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes less than 10 meters of a length of the subsea hydrocarbon pipeline, optionally including less than 7 meters, less than 5 meters, less than 3 meters, less than 2 meters, or less than 1 meter of the length of the subsea hydrocarbon pipeline.

F31. The method of any of paragraphs D1-F30, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a first inductively coupled portion of the subsea hydrocarbon pipeline, and wherein, subsequent to inductively heating the first inductively coupled portion of the subsea hydrocarbon pipeline, the method further includes inductively heating a second inductively coupled portion of the subsea hydrocarbon pipeline, wherein the first inductively coupled portion is different from the second inductively coupled portion.

F32. The method of any of paragraphs D1-F31, wherein the method further includes injecting an obstruction-dissolving compound into the subsea hydrocarbon pipeline.

F33. The method of paragraph F32, wherein the obstruction-dissolving compound includes at least one of methanol, ethylene glycol, a kinetic inhibitor, and an anti-agglomerate.

F34. The method of any of paragraphs F32-F33, wherein prior to the inductively heating, a fluid flow through the subsea hydrocarbon pipeline is occluded by the obstruction, wherein the inductively heating includes establishing a fluid flow within the subsea hydrocarbon pipeline by removing at least a portion of the obstruction, and further wherein the injecting includes injecting after the establishing.

G1. The use of a mobile subsea hydrocarbon pipeline induction heating assembly to remove a solids deposit from a subsea hydrocarbon pipeline.

G2. The use of a mobile subsea hydrocarbon pipeline induction heating assembly to inductively heat at least a portion of a subsea hydrocarbon pipeline.

G3. The use of a mobile subsea hydrocarbon pipeline induction heating assembly to increase a flow rate of a fluid stream within a subsea hydrocarbon pipeline.

G4. The use of the assembly of any of paragraphs A1-C55 with the method of any of paragraphs D1-F33.

G5. The use of the method of any of paragraphs D1-F34 with the assembly of any of paragraphs A1-C55.

G6. The use of the assembly of any of paragraphs A1-C55 or the method of any of paragraphs D1-F34 to inductively heat a subsea hydrocarbon pipeline.

G7. The use of the assembly of any of paragraphs A1-C55 or the method of any of paragraphs D1-F34 to remove an obstruction from a subsea hydrocarbon pipeline.

G8. The use of the assembly of any of paragraphs A1-C55 or the method of any of paragraphs D1-F34 to increase a flow rate of a fluid stream within a subsea hydrocarbon pipeline.

G9. The method of any of paragraphs D1-F33 performed using the apparatus of any of paragraphs A1-C55.

PCT1. A mobile subsea hydrocarbon pipeline heating assembly comprising:

a mobile subsea conveyance configured to traverse a selected portion of a subsea hydrocarbon pipeline; and

an inductive heating element that is operatively attached to the mobile subsea conveyance and configured to inductively heat an inductively coupled portion of the subsea hydrocarbon pipeline.

PCT2. The assembly of paragraph PCT1, wherein the mobile subsea conveyance includes at least one of a remotely operated vehicle and a propulsion mechanism.

PCT3. The assembly of any of paragraphs PCT1-PCT2, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline to melt an obstruction present within the subsea hydrocarbon pipeline, wherein the obstruction includes at least one of a wax, a hydrate, an asphaltene, and scale.

PCT4. The assembly of any of paragraphs PCT1-PCT3, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without at least one of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.

PCT5. The assembly of any of paragraphs PCT1-PCT4, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline while the fluid stream is flowing through the subsea hydrocarbon pipeline.

PCT6. The assembly of any of paragraphs PCT1-PCT5, wherein the subsea hydrocarbon pipeline includes a metallic conduit and an external coating, and further wherein the external coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.

PCT7. The assembly of any of paragraphs PCT1-PCT6, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a sub-portion of the selected portion of the subsea hydrocarbon pipeline, and further wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes less than 3 meters of a length of the subsea hydrocarbon pipeline.

PCT8. The assembly of any of paragraphs PCT1-PCT7, wherein the selected portion of the subsea hydrocarbon pipeline includes at least 10% of a length of the subsea hydrocarbon pipeline, and further wherein the length of the subsea hydrocarbon pipeline is at least 1 km.

PCT9. The assembly of any of paragraphs PCT1-PCT8, wherein the selected portion of the subsea hydrocarbon pipeline is determined based upon a variable associated with the selected portion of the subsea hydrocarbon pipeline, wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.

PCT10. A method of removing an obstruction from a subsea hydrocarbon pipeline, the method comprising:

inductively heating an inductively coupled portion of the subsea hydrocarbon pipeline with a mobile subsea hydrocarbon pipeline heating assembly.

PCT11. The method of paragraph PCT10, wherein prior to the inductively heating, the method includes moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the inductively coupled portion of the subsea hydrocarbon pipeline, and further wherein the method includes traversing at least a selected portion of a length of the subsea hydrocarbon pipeline and the inductively heating includes inductively heating the selected portion of the length of the subsea hydrocarbon pipeline.

PCT12. The method of any of paragraphs PCT10-PCT11, wherein the subsea hydrocarbon pipeline includes an external coating and the inductively heating includes inductively heating through the external coating without damage to the external coating, wherein the external coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.

PCT13. The method of any of paragraphs PCT10-PCT12, wherein the method further includes determining a selected portion of the subsea hydrocarbon pipeline to be inductively heated, wherein the inductively coupled portion forms a subset of the selected portion, wherein the determining includes determining based at least in part on a variable associated with the selected portion of the subsea hydrocarbon pipeline, and further wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.

PCT14. The method of any of paragraphs PCT10-PCT13, wherein the method further includes determining a selected portion of the subsea hydrocarbon pipeline to be inductively heated, wherein the inductively coupled portion forms a subset of the selected portion, wherein the determining includes determining based at least in part on a model of the subsea hydrocarbon pipeline, wherein the method includes predicting the formation of an obstruction within an obstructed portion of the subsea hydrocarbon pipeline using the model, and further wherein the selected portion of the subsea hydrocarbon pipeline includes the obstructed portion of the subsea hydrocarbon pipeline.

PCT15. The method of any of paragraphs PCT10-PCT14, wherein the method further includes transferring thermal energy from the subsea hydrocarbon pipeline to the obstruction, wherein the transferring includes melting at least a portion of the obstruction.

PCT16. The method of any of paragraphs PCT10-PCT15, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the method includes flowing the fluid stream through the fluid conduit concurrently with the inductively heating.

PCT17. The method of any of paragraphs PCT10-PCT16, wherein the method further includes injecting an obstruction-dissolving compound into the subsea hydrocarbon pipeline, wherein the obstruction-dissolving compound includes at least one of methanol, ethylene glycol, a kinetic inhibitor, and an anti-agglomerate.

INDUSTRIAL APPLICABILITY

The systems and methods disclosed herein are applicable to the oil and gas industry.

It is believed that the disclosure set forth above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed herein. Similarly, where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.

It is believed that the following claims particularly point out certain combinations and subcombinations that are directed to one of the disclosed inventions and are novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower, or equal in scope to the original claims, are also regarded as included within the subject matter of the inventions of the present disclosure. 

1. A mobile subsea hydrocarbon pipeline heating assembly, comprising: a mobile subsea conveyance configured to traverse a selected portion of a subsea hydrocarbon pipeline; and an inductive heating element that is operatively attached to the mobile subsea conveyance and configured to inductively heat an inductively coupled portion of the subsea hydrocarbon pipeline.
 2. The assembly of any of claim 1, wherein the mobile subsea conveyance includes a remotely operated vehicle.
 3. The assembly of claim 1, wherein the mobile subsea conveyance includes a propulsion mechanism.
 4. The assembly of claim 1, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes a sub-portion of the selected portion of the subsea hydrocarbon pipeline.
 5. The assembly of claim 4, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes less than 3 meters of a length of the subsea hydrocarbon pipeline.
 6. The assembly of claim 5, wherein the selected portion of the subsea hydrocarbon pipeline includes at least 10% of a length of the subsea hydrocarbon pipeline.
 7. The assembly of claim 6, wherein the length of the subsea hydrocarbon pipeline is at least 1 km.
 8. The assembly of claim 5, wherein the selected portion of the subsea hydrocarbon pipeline is determined based upon a variable associated with the selected portion of the subsea hydrocarbon pipeline.
 9. The assembly of claim 8, wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.
 10. The assembly of claim 5, wherein the selected portion of the subsea hydrocarbon pipeline is determined based at least in part upon a model of the subsea hydrocarbon pipeline, wherein the model is configured to predict the formation of an obstruction within an obstructed portion of the subsea hydrocarbon pipeline, and further wherein the selected portion of the subsea hydrocarbon pipeline includes the obstructed portion of the subsea hydrocarbon pipeline.
 11. The assembly of claim 1, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline to melt an obstruction present within the subsea hydrocarbon pipeline, wherein the obstruction includes at least one of a wax, a hydrate, an asphaltene, and scale.
 12. The assembly of claim 1, wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline without at least one of physical, mechanical, electrical, and thermal contact between the inductive heating element and the subsea hydrocarbon pipeline.
 13. The assembly of claim 1, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the mobile subsea hydrocarbon pipeline heating assembly is configured to inductively heat the inductively coupled portion of the subsea hydrocarbon pipeline while the fluid stream is flowing through the subsea hydrocarbon pipeline.
 14. The assembly of claim 1, wherein the subsea hydrocarbon pipeline includes a metallic conduit and an external coating, and further wherein the external coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.
 15. A mobile subsea hydrocarbon pipeline heating assembly, comprising: means for inductively heating an inductively coupled portion of a subsea hydrocarbon pipeline; and means for moving the means for inductively heating along a selected portion of a length of the subsea hydrocarbon pipeline.
 16. A method of removing an obstruction from a subsea hydrocarbon pipeline, the method comprising: inductively heating an inductively coupled portion of the subsea hydrocarbon pipeline with a mobile subsea hydrocarbon pipeline heating assembly.
 17. The method of claim 16, wherein prior to the inductively heating, the method includes moving the mobile subsea hydrocarbon pipeline heating assembly into inductive communication with the inductively coupled portion of the subsea hydrocarbon pipeline.
 18. The method of claim 17, wherein the moving includes moving the mobile subsea hydrocarbon pipeline heating assembly from inductive communication with a previously inductively coupled portion of the subsea hydrocarbon pipeline and into inductive communication with a subsequently inductively coupled portion of the subsea hydrocarbon pipeline.
 19. The method of claim 16, wherein the method further includes traversing at least a selected portion of a length of the subsea hydrocarbon pipeline, and the inductively heating includes inductively heating the selected portion of the length of the subsea hydrocarbon pipeline.
 20. The method of claim 16, wherein the subsea hydrocarbon pipeline includes an external coating and the inductively heating includes inductively heating through the external coating without damage to the external coating.
 21. The method of claim 20, wherein the external coating includes at least one of thermal insulation, electrical insulation, and a corrosion-resistant coating.
 22. The method of claim 16, wherein the inductively heating includes inductively heating without at least one of physical, mechanical, electrical, and thermal contact between an inductive heating element configured to provide the inductive heating and the subsea hydrocarbon pipeline.
 23. The method of claim 16, wherein the method further includes determining a selected portion of the subsea hydrocarbon pipeline to be inductively heated, wherein the inductively coupled portion forms a subset of the selected portion.
 24. The method of claim 23, wherein the determining includes determining based at least in part on a variable associated with the selected portion of the subsea hydrocarbon pipeline, and further wherein the variable associated with the selected portion of the subsea hydrocarbon pipeline includes at least one of a temperature and a pressure associated with the selected portion of the subsea hydrocarbon pipeline.
 25. The method of claim 23, wherein the determining includes determining based at least in part on a model of the subsea hydrocarbon pipeline, wherein the method includes predicting the formation of an obstruction within an obstructed portion of the subsea hydrocarbon pipeline using the model, and further wherein the selected portion of the subsea hydrocarbon pipeline includes the obstructed portion of the subsea hydrocarbon pipeline.
 26. The method of claim 16, wherein the method further includes transferring thermal energy from the subsea hydrocarbon pipeline to the obstruction, wherein the transferring includes melting at least a portion of the obstruction.
 27. The method of claim 16, wherein the subsea hydrocarbon pipeline is configured to provide a fluid conduit for a flow of a fluid stream therethrough, and further wherein the method includes flowing the fluid stream through the fluid conduit concurrently with the inductively heating.
 28. The method of claim 16, wherein the inductively coupled portion of the subsea hydrocarbon pipeline includes less than 3 meters of a length of the subsea hydrocarbon pipeline.
 29. The method of claim 16, wherein the method further includes injecting an obstruction-dissolving compound into the subsea hydrocarbon pipeline, wherein the obstruction-dissolving compound includes at least one of methanol, ethylene glycol, a kinetic inhibitor, and an anti-agglomerate. 